Add lvm_errno and lvm_errmsg to liblvm to obtain failure information.

Change create_toolcontext to still return an object if it fails part-way.
Add EUNCLASSIFIED (-1) as the default LVM errno code.

WHATS_NEW

@@ -1,5 +1,8 @@
 Version 2.02.50 - 
 ================================
+  Add lvm_errno and lvm_errmsg to liblvm to obtain failure information.
+  Change create_toolcontext to still return an object if it fails part-way.
+  Add EUNCLASSIFIED (-1) as the default LVM errno code.
   Store any errno and error messages issued while processing each command.
   Use log_error macro consistently throughout in place of log_err.
 

daemons/clvmd/lvm-functions.c

@@ -792,6 +792,11 @@ int init_lvm(int using_gulm)
 		return 0;
 	}
 
+	if (stored_errno()) {
+		destroy_toolcontext(cmd);
+		return 0;
+	}
+
 	/* Use LOG_DAEMON for syslog messages instead of LOG_USER */
 	init_syslog(LOG_DAEMON);
 	openlog("clvmd", LOG_PID, LOG_DAEMON);

lib/commands/toolcontext.c

@@ -1083,6 +1083,9 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
 	dm_list_init(&cmd->tags);
 	dm_list_init(&cmd->config_files);
 
+	/* FIXME Make this configurable? */
+	reset_lvm_errno(1);
+
 	/*
 	 * Environment variable LVM_SYSTEM_DIR overrides this below.
 	 */
@@ -1092,7 +1095,7 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
 		strcpy(cmd->system_dir, DEFAULT_SYS_DIR);
 
 	if (!_get_env_vars(cmd))
-		goto error;
+		goto_out;
 
 	/* Create system directory if it doesn't already exist */
 	if (*cmd->system_dir && !dm_create_dir(cmd->system_dir)) {
@@ -1100,58 +1103,58 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
 			  "files and internal cache.");
 		log_error("Set environment variable LVM_SYSTEM_DIR to alternative location "
 			  "or empty string.");
-		goto error;
+		goto out;
 	}
 
 	if (!(cmd->libmem = dm_pool_create("library", 4 * 1024))) {
 		log_error("Library memory pool creation failed");
-		goto error;
+		goto out;
 	}
 
 	if (!_init_lvm_conf(cmd))
-		goto error;
+		goto_out;
 
 	_init_logging(cmd);
 
 	if (!_init_hostname(cmd))
-		goto error;
+		goto_out;
 
 	if (!_init_tags(cmd, cmd->cft))
-		goto error;
+		goto_out;
 
 	if (!_init_tag_configs(cmd))
-		goto error;
+		goto_out;
 
 	if (!_merge_config_files(cmd))
-		goto error;
+		goto_out;
 
 	if (!_process_config(cmd))
-		goto error;
+		goto_out;
 
 	if (!_init_dev_cache(cmd))
-		goto error;
+		goto_out;
 
 	if (!_init_filters(cmd, 1))
-		goto error;
+		goto_out;
 
 	if (!(cmd->mem = dm_pool_create("command", 4 * 1024))) {
 		log_error("Command memory pool creation failed");
-		goto error;
+		goto out;
 	}
 
 	memlock_init(cmd);
 
 	if (!_init_formats(cmd))
-		goto error;
+		goto_out;
 
 	if (!init_lvmcache_orphans(cmd))
-		goto error;
+		goto_out;
 
 	if (!_init_segtypes(cmd))
-		goto error;
+		goto_out;
 
 	if (!_init_backup(cmd))
-		goto error;
+		goto_out;
 
 	_init_rand(cmd);
 
@@ -1161,20 +1164,8 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
 	cmd->current_settings = cmd->default_settings;
 
 	cmd->config_valid = 1;
-	reset_lvm_errno(1);  /* FIXME Move to top when cmd returned on error */
+out:
 	return cmd;
-
-      error:
-	_destroy_tag_configs(cmd);
-	dev_cache_exit();
-	if (cmd->filter)
-		cmd->filter->destroy(cmd->filter);
-	if (cmd->mem)
-		dm_pool_destroy(cmd->mem);
-	if (cmd->libmem)
-		dm_pool_destroy(cmd->libmem);
-	dm_free(cmd);
-	return NULL;
 }
 
 static void _destroy_formats(struct dm_list *formats)

lib/log/log.c

@@ -152,12 +152,12 @@ void reset_lvm_errno(int store_errmsg)
 	_store_errmsg = store_errmsg;
 }
 
-int lvm_errno(void)
+int stored_errno(void)
 {
 	return _lvm_errno;
 }
 
-const char *lvm_errmsg(void)
+const char *stored_errmsg(void)
 {
 	return _lvm_errmsg ? : "";
 }

lib/log/lvm-logging.h

@@ -20,7 +20,8 @@ void print_log(int level, const char *file, int line, int dm_errno,
 	       const char *format, ...)
     __attribute__ ((format(printf, 5, 6)));
 
-#define LOG_LINE(l, x...) print_log(l, __FILE__, __LINE__ , 0, ## x)
+#define EUNCLASSIFIED -1	/* Generic error code */
+#define LOG_LINE(l, x...) print_log(l, __FILE__, __LINE__ , EUNCLASSIFIED, ## x)
 
 #include "log.h"
 
@@ -44,8 +45,8 @@ void fin_syslog(void);
 
 int error_message_produced(void);
 void reset_lvm_errno(int store_errmsg);
-int lvm_errno(void);
-const char *lvm_errmsg(void);
+int stored_errno(void);
+const char *stored_errmsg(void);
 
 /* Suppress messages to stdout/stderr (1) or everywhere (2) */
 /* Returns previous setting */

liblvm/lvm_base.c

@@ -29,6 +29,10 @@ lvm_t lvm_create(const char *system_dir)
 	cmd = create_toolcontext(1, system_dir);
 	if (!cmd)
 		return NULL;
+
+	if (stored_errno())
+		return (lvm_t) cmd;
+
 	/*
 	 * FIXME: if an non memory error occured, return the cmd (maybe some
 	 * cleanup needed).
@@ -66,3 +70,13 @@ int lvm_reload_config(lvm_t libh)
 	/* FIXME: re-init locking needed here? */
 	return refresh_toolcontext((struct cmd_context *)libh);
 }
+
+int lvm_errno(lvm_t libh)
+{
+	return stored_errno();
+}
+
+const char *lvm_errmsg(lvm_t libh)
+{
+	return stored_errmsg();
+}

tools/lvmcmdline.c

@@ -1181,6 +1181,11 @@ struct cmd_context *init_lvm(void)
 	if (!(cmd = create_toolcontext(0, NULL)))
 		return_NULL;
 
+	if (stored_errno()) {
+		destroy_toolcontext(cmd);
+		return_NULL;
+	}
+
 	return cmd;
 }